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<a name="libgimpmath3-GimpMath"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle"><a name="libgimpmath3-GimpMath.top_of_page"></a>GimpMath</span></h2>
<p>GimpMath — Mathematical definitions and macros.</p>
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<div class="refsect1">
<a name="libgimpmath3-GimpMath.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_proto_type">
<col class="functions_proto_name">
</colgroup>
<tbody>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#RINT:CAPS" title="RINT()">RINT</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#ROUND:CAPS" title="ROUND()">ROUND</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#SIGNED-ROUND:CAPS" title="SIGNED_ROUND()">SIGNED_ROUND</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#SQR:CAPS" title="SQR()">SQR</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#MAX255:CAPS" title="MAX255()">MAX255</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#CLAMP0255:CAPS" title="CLAMP0255()">CLAMP0255</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#SAFE-CLAMP:CAPS" title="SAFE_CLAMP()">SAFE_CLAMP</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#gimp-deg-to-rad" title="gimp_deg_to_rad()">gimp_deg_to_rad</a><span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name">
<a class="link" href="libgimpmath3-GimpMath.html#gimp-rad-to-deg" title="gimp_rad_to_deg()">gimp_rad_to_deg</a><span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="libgimpmath3-GimpMath.description"></a><h2>Description</h2>
<p>Mathematical definitions and macros for use both by the GIMP
application and plug-ins. These macros should be used rather than
the ones from &lt;math.h&gt; for enhanced portability.</p>
</div>
<div class="refsect1">
<a name="libgimpmath3-GimpMath.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="RINT:CAPS"></a><h3>RINT()</h3>
<pre class="programlisting">#define RINT(x) rint(x)
</pre>
<p>This macro rounds its argument <em class="parameter"><code>x</code></em>
 to an integer value in floating
point format. Use <a class="link" href="libgimpmath3-GimpMath.html#RINT:CAPS" title="RINT()"><code class="function">RINT()</code></a> instead of <code class="function">rint()</code>.</p>
<div class="refsect3">
<a name="RINT.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>the value to be rounded</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="ROUND:CAPS"></a><h3>ROUND()</h3>
<pre class="programlisting">#define ROUND(x) ((int) ((x) + 0.5))
</pre>
<p>This macro rounds its positive argument <em class="parameter"><code>x</code></em>
 to the nearest integer.</p>
<div class="refsect3">
<a name="ROUND.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>the value to be rounded.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="SIGNED-ROUND:CAPS"></a><h3>SIGNED_ROUND()</h3>
<pre class="programlisting">#define SIGNED_ROUND(x) ((int) RINT (x))
</pre>
<p>This macro rounds its argument <em class="parameter"><code>x</code></em>
 to the nearest integer.</p>
<div class="refsect3">
<a name="SIGNED-ROUND.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>the value to be rounded.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="SQR:CAPS"></a><h3>SQR()</h3>
<pre class="programlisting">#define SQR(x) ((x) * (x))
</pre>
<p>This macro squares its argument <em class="parameter"><code>x</code></em>
.</p>
<div class="refsect3">
<a name="SQR.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>the value to be squared.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="MAX255:CAPS"></a><h3>MAX255()</h3>
<pre class="programlisting">#define MAX255(a)  ((a) | (((a) &amp; 256) - (((a) &amp; 256) &gt;&gt; 8)))
</pre>
<p>This macro limits it argument <em class="parameter"><code>a</code></em>
, an (0-511) int, to 255.</p>
<div class="refsect3">
<a name="MAX255.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>a</p></td>
<td class="parameter_description"><p>the value to be limited.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="CLAMP0255:CAPS"></a><h3>CLAMP0255()</h3>
<pre class="programlisting">#define CLAMP0255(a)  CLAMP(a,0,255)
</pre>
<p>This macro clamps its argument <em class="parameter"><code>a</code></em>
, an int32-range int, between 0
and 255 inclusive.</p>
<div class="refsect3">
<a name="CLAMP0255.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>a</p></td>
<td class="parameter_description"><p>the value to be clamped.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="SAFE-CLAMP:CAPS"></a><h3>SAFE_CLAMP()</h3>
<pre class="programlisting">#define SAFE_CLAMP(x, low, high)  ((x) &gt; (low) ? (x) &lt; (high) ? (x) : (high) : (low))
</pre>
<p>Ensures that <em class="parameter"><code>x</code></em>
 is between the limits set by <em class="parameter"><code>low</code></em>
 and <em class="parameter"><code>high</code></em>
,
even if <em class="parameter"><code>x</code></em>
 is NaN. If <em class="parameter"><code>low</code></em>
 is greater than <em class="parameter"><code>high</code></em>
, or if either
of them is NaN, the result is undefined.</p>
<div class="refsect3">
<a name="SAFE-CLAMP.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>x</p></td>
<td class="parameter_description"><p>the value to be limited.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>low</p></td>
<td class="parameter_description"><p>the lower limit.</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>high</p></td>
<td class="parameter_description"><p>the upper limit.</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<p class="since">Since: <a class="link" href="api-index-2-10.html#api-index-2.10">2.10</a></p>
</div>
<hr>
<div class="refsect2">
<a name="gimp-deg-to-rad"></a><h3>gimp_deg_to_rad()</h3>
<pre class="programlisting">#define gimp_deg_to_rad(angle) ((angle) * (2.0 * G_PI) / 360.0)
</pre>
<p>This macro converts its argument <em class="parameter"><code>angle</code></em>
 from degree to radian.</p>
<div class="refsect3">
<a name="gimp-deg-to-rad.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>angle</p></td>
<td class="parameter_description"><p>the angle to be converted.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="gimp-rad-to-deg"></a><h3>gimp_rad_to_deg()</h3>
<pre class="programlisting">#define gimp_rad_to_deg(angle) ((angle) * 360.0 / (2.0 * G_PI))
</pre>
<p>This macro converts its argument <em class="parameter"><code>angle</code></em>
 from radian to degree.</p>
<div class="refsect3">
<a name="gimp-rad-to-deg.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>angle</p></td>
<td class="parameter_description"><p>the angle to be converted.</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
</div>
</div>
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